TH400 Transmission Slip Yoke 1350 Series 32 Spline 3-3-2431X

This is a 1350 series transmission slip yoke for GM transmissions with the 32-spline output shaft. It replaces 3-3-2431X (332431X) and interchanges with Neapco N3-3-2431X and Sonnax T3-3-2431CBH and T3-3-2431CBHP. Fitment covers the Turbo 400 (TH400), 4L80E and 4L85E automatics, plus Muncie M20, M21 and M22, Richmond, Jericho and Borg Warner Super T10 manual boxes with the 32-spline output.

Moving a TH400 or 4L80E build to a 1350 driveshaft is a common step once horsepower or tire size goes up, since the larger 1350 joint handles more torque than a 1310. A new yoke is also the fix when the old one has a worn, grooved sealing surface. That groove chews up the tailhousing seal and leads to a fluid leak at the back of the transmission.

Before installing, check the tailhousing bushing for wear and replace the rear seal. Slide the yoke on by hand to confirm the splines engage smoothly, and put a light coat of transmission fluid on the sealing surface. This yoke uses an outside snap ring style 1350 U-joint (5-1350X). With the driveshaft installed and the suspension at ride height, make sure there is enough spline engagement and room for the yoke to move in and out.